Distribution of matrix homopolymer in block copolymers of spherical morphology

Samples made by blending deuteriated polystyrene S sub d of three different molecular weights with a polystyrene--polybutadiene block copolymer SB were studied with small-angle scattering techniques using X-rays (SAXS) and neutrons (SANS). The SANS results were sensitive both to the amount of added homopolymer S sub d and to its chain length. Anomalously high SANS intensities and the absence of an intraparticle scattering maximum are consistent with the exclusion of added S sub d from the corona of the SB micelles, resulting in S sub d enrichment of the interstitial regions. 24 ref.--AA